Knife sharpener



M. T. .GBAF. KNIFE SHARPENER.

APPLICATION FILED MAR. I4, 192!- Patented May 23, 1922. 7

inanrrn r. sitar, or BUFFALO, new "roan, assrsnon or nun-Hahn 'ro rnanirIRE, OI BUFFALO, NEW YORK.

KNIFE SHARPENER.

Application filed March 14,

To all whom it may concern: 1

Be it known that I, MARTIN T. Gear, a citizen of the United States,residing in Buffalo, in the county of Erie and State of New York, haveinvented new and useful Improvements in Knife Sharpeners, of which thefollowing is a specification.

This invention relates to a knife sharpener which is more particularlydesigned for sharpening kitchen knives and the like.

It is the object of this inventionto produce a sharpener for thispurpose which i will permitof readily and conveniently putting a keencutting edge on a knife, either on one or both sides thereof, by drawingthe knife one or more times past the sharpening surface of the tool, andso constructing this sharpener that the same can be produced atcomparatively low cost, that the same will be safe in use, that thecutting teeth will re @lmain sharp for a comparatively long time andthat the cutting teeth of the same will i be cleared. of chips ormetallic dust and plan view of the same.

therefore not become clogged so that the cuttin efficiency 1s notimpaired.

In t 1e accompanying drawings: Figure 1 is an elevation of the preferredform of my improved knife sharpener. Figure 2 is a top Figure 3 is avertical longitudinal section thereof, taken on the correspondinglynumbered line in Fl 52.

Figure 4 is a vertical transverse section of the same. Figure 5 is afragmentary hori zontal section on an enlarged scale, taken on line 5-5,Fig.1, and showing the manner in. which the blade or knife is engagedwith one or the other cutting surfaces of the, sharpening tool. Figure 6is a perspective view of a pair of blades orsharpener sec tions whichtogether form the sharpening member of the tool. Figure 7 is afragmentary longitudinal section of one of the sharpening blades, on agreatly enlarged scale, for the purpose of showing the form of thecutting teeth, ribs, ridges, or corru gations. y Similar characters ofreference refer to like parts throughout the several views.

The holder of the knife sharpener is preferably constructed of a bar 10of wood which i is substantially rectangular in cross section and ofsufficient length so that the end 11 thereof will serve as the handle ofthe tool, while the other end 12 forms the shank upon which thesharpening devices are mounted,

Specification of Letters Patent.

Patented May 23, 183

of each notch has its rear part 16 arranged parallelwith thecorresponding inner side 15, while the front part 17 of this outer sideis inclined relatively to the companion rearpart thereof, so that thenarrow rear part of this notch forms a seat which is of rectangular formin cross section and the front inclined part l'Z' of the outer sideforms a guiding surface against which the knife blade 18 may be restedduring the operation of sharpening the same. In each of these notches isarranged a sharpening blade 19 of steel or other suitable material.

which blade preferably has a plain inner or rear surface 20 while itsouter or front surface is constructed to form a cuttingsurface overwhich the edge of the'knife blade may be drawn for sharpening the same.Each of these sharpening blades has its rear end engaged with the narrowrear part of one of the notches which forms a seat therefor, so that therear side ofthe blade engages with the transverse inner side of therespective notch and the front part of the opposite or cutting;surfaceof the blade is arranged opposite the inclined guiding surface 17of the respective notch, as best shown in Figs. 1 and 3. i y

The two sharpening blades or sections which together constitute thecuttingele ment of the knife sharpener are held in their respectivenotches by means which are so constructed that they hold both blades inplace at thesame time, and thereby simplify the construction of the tooland also effect a considerable economy in the manufacture of the same.

In its preferred construction this fastening device comprises a frontwasher 21 i which engages with the front ends of both sharpening blades,a rear washer 22 seated in a recess 23 formed in the opposite or rearedge of the holder bar and a rivet 24% extending transversely throughthe partltion which separates the notches and engages its oppositeenlarged ends with the outer sides of said washers.

During the operation of sharpening a knife the blade of the same isalternately drawn lengthwise through the spaces between opposite cuttingsurfaces of the blades and the inclined guide surfaces of the holderbar, during which operation the blade is rested in a transversely tiltedposition against these guide surfaces so as to produce the aroper bevelupon the cutting edge of the blat e. This operation is repeated as oftenas necessary to produce the desired cutting edge on the blade of theknife.

The cutting surface of each sharpening blade is preferably produced bymeans of a plurality of parallel cutting teeth, ribs, ridges orcorrugations 25 which are arranged on the front side or outer surface ofeach sharpening blade, the arrangement of these teeth being such thatthey stand at an obtuse angle relative to the direction in which theknife is drawn past these teeth during the sharpening operation or inother words, the same lean in the same direction in which the knife isdrawn when sharpening the same. By this arrangement of the teeth thecutting action of the same will not be too pronounced and still asufficient shearing action of the same is obtained on the metal of theknife blade which will produce a sharpening effect on the same, therebyproducing a sharpening effect without undue loss of metal and wearingdown the knife blade unnecessarily.

In order to further reduce the cutting effect of these teetlneach toothis so constructed that its front side or face 26 is arranged at anobtuse or steep angle relative to the direction in which the knife bladeis to be sharpened is drawn past the same. while the rear side or face27 of each cutter tooth is arranged at an acute or flat angle relativelythereto, as best shown in Fig. 7. By this means a rearward movement ofthe knife blade relative to the sharpening surface of each sharpeningblade will have no sharpening effect on the same. but upon drawing theknife blade forwardly past the cutter teeth while in engagementtherewith the outer edge or corner of eachsharpening tooth will producea mild sharpening or abrading action upon the knife blade which willsharpen the latter without liability of the tooth digging into the metalof the knife blade and unduly wearing the same or producing a roughenedsurface thereon which otherwise would be the case.

In order to enable the sharpening of the knife blade to be effected bydrawing the knife blade in thesame direction against both sharpeningsurfaces of the sharpening blades, the cutting teeth, ribs or ridges ofthe two sharpening blades which face in opposite directions, arearranged to slope or incline in the same direction and preferably at thesame angle. as best shown in Fig. ll. By this means either or both sidesof the knife blade can be sharpened by drawing the blade from the frontside of the sharp-- cner toward the rear side of the same. thus avoidingimproper use of the tool whilc sharpening a knife blade.

Each of the sharpening blades is prcl'ci' ably narrower than the holderbar and lhc sameis arranged in itsrcspectivc notch in the holder midwaybetween opposite sh les ll icrco l so as to form pockets 28,28 in thenotches adjacent to the opposite longitudinal edges of each sharpeningblade as shown in Figs. :2. ti and By this means a clearing space isfurnished at opposite edges of each shar ening blade into which aredischarged the small cuttings, metallic dust or chips re moved from theknife blade which is liLii]!.'.' sharpened. which chips in the absenceof such provision would be liable to (flog lhc teeth of the sharpeningblades and reduce their efficiency.

As a whole this knife sharpener is very simple and inexpensive inconstruction and permits of eliiciently and quickly putting :1 keen edgeon a knife blade by simply drawing the edge of the same one or moretimes past the surfaces of the cutting blades in the manner described.

I claim as my invention 1. A knife sharpener comprising a holder barwhich is provided on one side with a laterally opening notch and on itsopposite side with a recess. a sharpening blade sealed in said notch, awasher engaging with the outer end of said blade. a washer sealed insaid recess, and a rivet passing through said bar and connecting said'ashers.

2. knife sharpener c'on'iprisiug a holder bar having two laterallyopening nolchcs arranged side by side and separated by an interveningpartition, sharpening blades seated in said notches, and a fasteningdcvice engaging the outer ends o l both of said blades and extendinginto said partition.

A knife sharpener comprising a holder bar having two laterally openingnotches arranged side by side and separated by an intervening partition,sharpening blades seated in said notches, and a fastening deviceextending through said partition and engaging with the outer ends ofsaid blades and with that side of said bar opposile to the notchesthereof.

M ARTIN T. GR A. F

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